1. Technical Field
The present invention relates to a liquid ejecting apparatus.
2. Related Art
There is developed a liquid ejecting apparatus configured to incise or excise living tissues by pressurizing liquid such as water or physiologic saline and ejecting the liquid toward the living tissues from a nozzle that has a reduced cross-sectional area. A surgical operation using such a liquid ejecting apparatus enables incision or excision of living tissues such as internal organs exclusively and selectively without damaging nerves, blood vessels or the like, and causes less damage to peripheral tissues. Therefore, burdens on patients can be reduced.
In addition, there is proposed a liquid ejecting apparatus which enables incision and excision of living tissues with a small ejecting amount by causing liquid to be ejected in a pulsed manner instead of simply causing the liquid to be ejected continuously from a nozzle (for example, see JP-A-2008-082202). Such a liquid ejecting apparatus is configured to abruptly raise the pressure in a liquid chamber that is filled with liquid by abruptly reducing the volume of the liquid chamber. This causes the liquid to be ejected from a nozzle connected to the liquid chamber in a pulsed manner using the increased pressure. Subsequently, the volume of the liquid chamber is restored and the liquid chamber is again filled. By repeating such actions, a pulsed jet stream is cyclically generated.
However, such a liquid ejecting apparatus configured to eject liquid in a pulsed manner suffers in that incising and excising performance tends to deteriorate due to accumulation of air bubbles existing in the liquid or air bubbles generated from air dissolved in the liquid under certain conditions in the liquid chamber. In other words, as described above, since a pulsed jet stream is generated by pressurizing the liquid in the liquid chamber by reducing the volume of the liquid chamber, if there exists air bubbles in the liquid chamber, the liquid cannot be pressurized sufficiently because such air bubbles are compressed when the volume of the liquid chamber is reduced. Therefore, the pulsed ejection of liquid from the nozzle cannot be achieved, and hence the incising and excising performances are disadvantageously lowered.